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Krill are small crustaceans of the order Euphausiacea, and are found in all the world's oceans. The name ''krill'' comes from the Norwegian word ', meaning "small fry of fish",〔(【引用サイトリンク】title=Krill )〕 which is also often attributed to other species of fish. Krill are considered an important trophic level connection – near the bottom of the food chain – because they feed on phytoplankton and to a lesser extent zooplankton, converting these into a form suitable for many larger animals for whom krill makes up the largest part of their diet. In the Southern Ocean, one species, the Antarctic krill, ''Euphausia superba'', makes up an estimated biomass of around 379,000,000 tonnes, more than that of humans. Of this, over half is eaten by whales, seals, penguins, squid and fish each year, and is replaced by growth and reproduction. Most krill species display large daily vertical migrations, thus providing food for predators near the surface at night and in deeper waters during the day. Krill is fished commercially in the Southern Ocean and in the waters around Japan. The total global harvest amounts to 150,000–200,000 tonnes annually, most of this from the Scotia Sea. Most of the krill catch is used for aquaculture and aquarium feeds, as bait in sport fishing, or in the pharmaceutical industry. In Japan, Philippines and Russia, krill is also used for human consumption and is known as in Japan. In the Philippines, it is known as "alamang" and it is used to make a salty paste called bagoong. Krill is also the main prey of baleen whales, including the blue whale. == Taxonomy == Krill belong to the large arthropod subphylum, the Crustacea. The most familiar and largest group of crustaceans, the class Malacostraca, includes the superorder Eucarida comprising the three orders, Euphausiacea (krill), Decapoda (shrimp, prawns, lobsters, crabs), and the planktonic ''Amphionides''. The order Euphausiacea comprises two families. The more abundant Euphausiidae contains ten different genera with a total of 85 species. Of these, the genus ''Euphausia'' is the largest, with 31 species. The lesser known family, the Bentheuphausiidae, has only one species, ''Bentheuphausia amblyops'', a bathypelagic krill living in deep waters below . It is considered the most primitive extant krill species. Well-known species of the Euphausiidae of commercial krill fisheries include Antarctic krill (''Euphausia superba''), Pacific krill (''Euphausia pacifica'') and Northern krill (''Meganyctiphanes norvegica''). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Krill」の詳細全文を読む スポンサード リンク
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